Safety lock

ABSTRACT

A key-operated, releasable safety-lock of the pin tumbler cylinder type wherein the pin tumblers may project outwards from radial bores accommodating same in the stationary cylindrical outer casing, said pin tumblers being urged inwards by an outer pin-biasing, elastic sleeve tightly enclosing said casing and covering said radial bores and pin tumblers.

Unite States Patent [191 Lipschutz Mar. 27, 1973 SAFETY LOCK [75] Inventor: Paul Lipschutz, Croissy-sur-Siene,

France [73] Assignee: Societe dExploitation des Brevets Neiman, Neuilly-sur-Seine, France [22] Filed: June 14, 1971 [21] Appl. No.: 152,798

[52] US. Cl. ..70/364 A, 70/372, 70/DIG. 74 [5 1] Int. Cl. ..E05b 15/00 [58] Field of Search ..70/358, 364 R, 363, 364 A,

70/372, 431, 447, DIG. 74, DIG. 55

[56] References Cited UNITED STATES PATENTS 1,929,235 10/1933 Bevington ..70/358 X 2,588,230 3/1952 George ..70/363 FOREIGN PATENTS OR APPLICATIONS 1,060,737 7/l959 Germany ..70/364R 597,009 8/1959 Italy ..70/364A Primary Examiner-Robert L. Wolfe Att0rney-Albert C. Nolte et a1.

[ ABSTRACT A key-operated, releasable safety-lock of the pin tumbler cylinder type wherein the pin tumblers may project outwards from radial bores accommodating same in the stationary cylindrical outer casing, said pin tumblers being urged inwards by an outer pin-biasing, elastic sleeve tightly enclosing said casing and covering said radial bores and pin tumblers.

6 Claims, 5 Drawing Figures SAFETY LOCK The invention relates to an improvement in locks of the type known as piston or pin tumbler cylinder locks.

This type of lock essentially comprises a fixed outer body or stator, an inner cylinder, plug or rotor constituting the rotating part of the lock and pin tumblers or pistons set in the stator and rotor, respectively, and engaging recesses in the rotor under the pressure of springs. A key engaging a central recess or keyway in the rotor is adapted to push the stator pistons back into the stator and enable the rotor to rotate freely.

In locks of this type hitherto produced, the return springs of the pistons consisted of coil springs engaging a recess in the stator. This recess would occupy a considerable amount of space in the stator and thus considerably increase the overall bulk of the lock. Moreover, this recess was difficult to be made dustproof and was consequently liable to give trouble.

The invention provides a novel method of constructing the elastic return of the pistons into their recess; this essentially consists in substituting for the metal springs, whose accommodation in the stationary part of the lock requires a considerable increase in the diameter of the lock, a sleeve made of rubber or elastic plastics. This sleeve may be or not provided with slots to ensure functional independence of the return mechanism for each piston, the said sleeve surrounding the stator and covering the apertures of the bores containing the pistons.

An embodiment of the invention is shown by way of example in the annexed drawing, in which:

FIG. 1 is a cross section through the lock according to the invention taken upon the line II of FIG. 4;

FIG. 2 is a side view of a slotted elastic sleeve;

FIG. 3 shows the same sleeve but without slots;

FIG. 4 shows an axial section through the lock with its key inserted in the rotor and with a slotted resilient sleeve;

FIG. 5 shows in a similar view the position of an elastic sleeve having no slots.

Referring to the drawing, it will be seen that the lock 1 consists of a casing or stator 2 having a central bore containing the rotor 3. The stator and rotor are formed with parallel cylindrical recesses la, lb opening into the central recess 3' which houses the key 4 which in this example has a cruciform profile. Each one of the cylindrical recesses in the stator and rotor which may be positioned by pairs through rotation of the rotor in substantially aligned or registering relationship houses a piston 5, 6. The piston 6 has a tapered tip 6' cooperating with a corresponding notch 4 formed in the key. The piston 5 is pushed inwards by an elastic sleeve which is fitted into an elongated groove 17 provided on the outer surface of the stator and extending over the axial length of the outer wall surface portion wherein open the cylindrical stator recesses la so that it is simultaneously in contact with all stator pistons 5.

According to FIG. 1, the rotor pistons 6, being pushed back by the notches of the key 4, exert their coaxial action on the stator counter-pistons 5 which thus distend the elastic sleeve 15 and so enable the key 4 to rotate the rotor 3 together with the remainder of the mechanism known under the general name of rotor" when the surface of separation between the pistons 5 and 6 is in alignment with the external cylindrical surface of separation 12 between the stator 2 and rotor 3 if the combination of notches 4 is correct.

According to the FIG. 2, the elastic sleeve 15 has or has not slots 16 formed over a limited portion of its periphery so as to ensure, if desired, the independent displacement of each piston 6, each of which pistons is associated with a particular strip 18 formed between two successive slots 16.

Owing to this arrangement, the whole resiliently expansible sleeve 15 will have a resistance'and strength which it could not have if it were composed of several independent rings, and at the same time this arrangement reinforces the elastic action of each one of the strips 18.

FIG. 4 clearly shows in longitudinal section the arrangement of the pistons pushed back by the notches of the key 4 and the displacements of the strips 18 under the pressure of the pistons 5.

It is obvious that this arrangement, illustrated here as applied to a single row of pistons, could equally well be applied to a diametrically opposite row or, if desired, to several rows of pistons evenly distributed over the lock barrel.

With dimensions much smaller than those required for the use of metal springs, the design of the sleeve for elastic recoil has the further advantage of ensuring that the whole lock is perfectly impervious to dust or the like.

Of course, the invention is by no means limited to the form of embodiment described and illustrated, which has been given by way of example only. In particular, it comprises all the means constituting technical equivalents to the means described as well as their combinations, should the latter be carried out according to the gist of the invention.

What we claim is:

1. A key-operated, releasable, safety-lock comprising: a substantially cylindrical, outer, stationary body formed with a longitudinal bore and with at least one plurality of radial bores opening into said longitudinal bore and arranged in at least one row in substantially parallel spaced relationship; a substantially cylindrical, inner, rotary plug rotatably housed with a substantially close-running fit in the mating longitudinal bore of said body and formed with a central, longitudinal keyhole and with at least one plurality of radial bores extending through the side wall of said plug to open to the outside and into said keyhole thereof, respectively, the radial bores of said plug being arranged in at least one row in substantially parallel spaced relationship and being adapted through rotation of said plug to register in substantially aligned relationship with the radial bores of said body; at least one plurality of key-responsive, spring-loaded, retractable pin tumbler means of differing lengths, slidably mounted in and engageable with said radial bores, respectively and adapted to project endwise into said keyhole; and a removable plug actuating key insertable in said keyhole and provided with notches, said pin tumbler means being resiliently urged inwards by spring means towards said keyhole in endwise engagement with said key notches; and wherein the improvement consists in that said radial bores of said body extend through the wall thereof to open to the outside, so that said pin tumbler means may project outwards from said radial bores, whereas said spring means consists of at least one annular outer yielding sleeve of elastic material tightly surrounding said body and covering the outer ends of said radial bores and pin tumbler means thereof.

4. A safety-lock according to claim 1, wherein said pin tumbler means are provided at their radially innermost ends with tapered tips.

5. A safety-lock according to claim 4, wherein each pin tumbler means consists of a pair of pin segments inserted in corresponding radial bores of said body and plug, respectively.

6. A safety-lock according to claim 1, wherein said key and keyhole are of substantially cruciform crosssection. 

1. A key-operated, releasable, safety-lock comprising: a substantially cylindrical, outer, stationary body formed with a longitudinal bore and with at least one plurality of radial bores opening into said longitudinal bore and arranged in at least one row in substantially parallel spaced relationship; a substantially cylindrical, inner, rotary plug rotatably housed with a substantially close-running fit in the mating longitudinal bore of said body and formed with a central, longitudinal keyhole and with at least one plurality of radial bores extending through the side wall of said plug to open to the outside and into said keyhole thereof, respectively, the radial bores of said plug being arranged in at least one row in substantially parallel spaced relationship and being adapted through rotation of said plug to register in substantially aligned relationship with the radial bores of said body; at least one plurality of keyresponsive, spring-loaded, retractable pin tumbler means of differing lengths, slidably mounted in and engageable with said radial bores, respectively and adapted to project endwise into said keyhole; and a removable plug-actuating key insertable in said keyhole and provided with notches, said pin tumbler means being resiliently urged inwards by spring means towards said keyhole in endwise engagement with said key notches; and wherein the improvement consists in that said radial bores of said body extend through the wall thereof to open to the outside, so that said pin tumbler means may project outwards from said radial bores, whereas said spring means consists of at least one annular outer yielding sleeve of elastic material tightly surrounding said body and covering the outer ends of said radial bores and pin tumbler means thereof.
 2. A safety-lock according to claim 1, wherein said sleeve is formed with at least one plurality of slots extending in substantially spaced, parallel relationship transversely of the longitudinaL axis of said sleeve along one portion of its circumferential periphery so as to define therein separate strips wide enough and adapted to cover the outward ends of the radial bores of said body and of said pin tumbler means, respectively.
 3. A safety lock according to claim 1, wherein said body is provided with a peripheral groove and said sleeve is recessed in said groove.
 4. A safety-lock according to claim 1, wherein said pin tumbler means are provided at their radially innermost ends with tapered tips.
 5. A safety-lock according to claim 4, wherein each pin tumbler means consists of a pair of pin segments inserted in corresponding radial bores of said body and plug, respectively.
 6. A safety-lock according to claim 1, wherein said key and keyhole are of substantially cruciform cross-section. 